time-to-botec

Benchmark sampling in different programming languages
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README.md (3309B)

      1 <!--
      2 
      3 @license Apache-2.0
      4 
      5 Copyright (c) 2018 The Stdlib Authors.
      6 
      7 Licensed under the Apache License, Version 2.0 (the "License");
      8 you may not use this file except in compliance with the License.
      9 You may obtain a copy of the License at
     10 
     11    http://www.apache.org/licenses/LICENSE-2.0
     12 
     13 Unless required by applicable law or agreed to in writing, software
     14 distributed under the License is distributed on an "AS IS" BASIS,
     15 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     16 See the License for the specific language governing permissions and
     17 limitations under the License.
     18 
     19 -->
     20 
     21 # mapKeys
     22 
     23 > Map keys from one object to a new object having the same values.
     24 
     25 <!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
     26 
     27 <section class="intro">
     28 
     29 </section>
     30 
     31 <!-- /.intro -->
     32 
     33 <!-- Package usage documentation. -->
     34 
     35 <section class="usage">
     36 
     37 ## Usage
     38 
     39 ```javascript
     40 var mapKeys = require( '@stdlib/utils/map-keys' );
     41 ```
     42 
     43 #### mapKeys( obj, transform )
     44 
     45 Map keys from one `object` to a new `object` having the same values.
     46 
     47 ```javascript
     48 function transform( key, value ) {
     49     return key + value;
     50 }
     51 
     52 var obj1 = {
     53     'a': 1,
     54     'b': 2
     55 };
     56 
     57 var obj2 = mapKeys( obj1, transform );
     58 // returns { 'a1': 1, 'b2': 2 }
     59 ```
     60 
     61 The `transform` function is provided three arguments:
     62 
     63 -   `key`: object key
     64 -   `value`: object value corresponding to `key`
     65 -   `obj`: the input object
     66 
     67 </section>
     68 
     69 <!-- /.usage -->
     70 
     71 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
     72 
     73 <section class="notes">
     74 
     75 ## Notes
     76 
     77 -   Key iteration order is **not** guaranteed, as `object` key enumeration is not specified according to the [ECMAScript specification][ecma-262-for-in]. In practice, however, most engines use insertion order to sort an `object`'s keys, thus allowing for deterministic return values.
     78 -   The function only maps **own** properties. Hence, the function does **not** map inherited properties.
     79 -   The function **shallow** copies key values.
     80 -   The value returned by a `transform` function should be a value which can be serialized as an `object` key.
     81 
     82 </section>
     83 
     84 <!-- /.notes -->
     85 
     86 <!-- Package usage examples. -->
     87 
     88 <section class="examples">
     89 
     90 ## Examples
     91 
     92 <!-- eslint no-undef: "error" -->
     93 
     94 ```javascript
     95 var mapKeys = require( '@stdlib/utils/map-keys' );
     96 
     97 function transform( key, value ) {
     98     return key + ':' + value;
     99 }
    100 
    101 var obj1 = {
    102     'a': 'beep',
    103     'b': 'boop',
    104     'c': 'foo',
    105     'd': 'bar'
    106 };
    107 
    108 var obj2 = mapKeys( obj1, transform );
    109 
    110 console.dir( obj2 );
    111 // => { 'a:beep': 'beep', 'b:boop': 'boop', 'c:foo': 'foo', 'd:bar': 'bar' }
    112 ```
    113 
    114 </section>
    115 
    116 <!-- /.examples -->
    117 
    118 <!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    119 
    120 <section class="references">
    121 
    122 </section>
    123 
    124 <!-- /.references -->
    125 
    126 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    127 
    128 <section class="links">
    129 
    130 [ecma-262-for-in]: http://www.ecma-international.org/ecma-262/5.1/#sec-12.6.4
    131 
    132 </section>
    133 
    134 <!-- /.links -->